In known wave-type weaving machines, the reed teeth are moved individually and the beating-up of the weft thread takes place over the width of the weaving machine continuously at individual regions. In the interests of good quality of the weave, the beating-up should take place at the same height at all the reed teeth. As a result, the beat-up line is given a straight course. Therefore, the pivoting movement is given to the reed teeth by means of a positive guide. But this must be provided with some play. The reason is that, in the case of an arrangement operating without any play, there would be a danger of overstressing some of the parts, since the reed teeth can be jammed under such conditions or even deformed.
In their beating-up movement, the reed teeth undergo a rapid decrease in speed and lose contact with the driving surface as a result of the play. The amount to which this contact is lost depends on the friction of the individual reed teeth and the force which is necessary for the beating-up. More particularly in the case of fabrics with a low weft density, a curved or undulating beat-up line can result. The aforesaid disadvantages are more likely to occur the faster the weaving machine is operated.
To obviate these disadvantages it is known to provide an elastic material against which the reed teeth strike shortly before reaching the beat-up position of the said reed teeth. By this measure, some progress is in fact made, but it is still necessary to tolerate some irregularities. If the elastic material is subjected to considerable stress, it forms an additional load on the driving arrangement. It also has the result that the distance required for stopping the reed teeth depends on the speed of the reed teeth. As a result, when the weaving machine is started, markings are produced in the fabric; finally, the stopping characteristic of the elastic material is different at different speed ranges of the reed teeth. This discussion is not intended to imply that providing an elastic material is always disadvantageous. The elastic material is found to be advantageous in particular if it is used to a suitably limited extent.
In connection with this application, the applicant is unaware of the existence of prior patented art.